The Turkish army has shelled Kurdish-held positions in northern Syria for a second day, a Turkish government official told Al Jazeera.
On Saturday, Turkey urged the fighters with the Syrian Kurdish People's Protection Units (YPG), the armed wing of the Syria's Democratic Union Party (PYD), to leave areas it captured in the northern part of the city of Aleppo.
The United States sees the PYD as a close ally in the campaign against Islamic State of Iraq and the Levant (ISIL) in Syria.
Ankara believes that the PYD is the Syrian wing of the Kurdistan Workers' Party (PKK), which has been locked in battle with Turkish forces for more than 30 years. The PKK is seen as a terrorist organisation by the U.S. and the European Union, while the PYD is not.
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An air base and other positions captured by the Kurdish fighters from opposition forces were targeted by Turkish army shelling on Saturday and Sunday.
The Syrian Observatory for Human Rights, a UK-based monitoring group, also reported the shelling, saying that two fighters died in Sunday's incident.
"The PYD is trying to carry out an ethnic cleansing by raiding areas where there is no or little Kurdish population and works to remove non-Kurdish ethnic elements out of these areas," Yasin Aktay, a government MP, told Al Jazeera.
"Aleppo is perhaps the only place where Syrians can still breathe. There is a humanitarian corridor [from Turkey] allowing people to still keep on going with their lives in this key city," said Aktay, who is also the ruling Justice and Development Party's deputy chairman responsible for foreign affairs.
"If this humanitarian corridor was cut, a goal aided by the PYD activities, people cannot go on with their lives in Aleppo and people will try to take refuge in Turkey fleeing ethnic cleansing."
Turkey has been warning the Kurdish fighters, which it sees as "terrorists", not to expand their positions since the beginning of the conflict in 2011. The YPG is in control of almost all of the Syrian-Turkish border.
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Prime Minister Ahmet Davutoglu said on Saturday that the shelling had taken place under "the rules of engagement against forces that represented a threat in Azaz and the surrounding area".
Aktay, the Turkish MP, said that Ankara could not tolerate what had been going on just outside its borders any more.
"If Turkish military do not intervene in the current situation, Turkey gets attacked by the elements located there. The US should see this fact. As an ally, the Washington administration should see that it cannot be friends with the enemies of Turkey," he told Al Jazeera.
Source: Al Jazeera